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// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.
//
// Description: the TextComposition class
//
using MS.Internal;
using MS.Win32;
using System;
using System.Diagnostics;
using System.Runtime.InteropServices;
using System.Windows;
using System.Windows.Input;
using System.Security;
namespace System.Windows.Documents
{
/// <summary>
/// the internal Composition class provides input-text/composition event promotion
/// This class is used for simple TextBox control that does not expose TextRange.
/// </summary>
public class FrameworkTextComposition: TextComposition
{
//------------------------------------------------------
//
// Constructors
//
//------------------------------------------------------
#region Constructors
//
// Constructor for TextStore's TextComposition.
//
internal FrameworkTextComposition(InputManager inputManager, IInputElement source, object owner) : base(inputManager, source, String.Empty, TextCompositionAutoComplete.Off)
{
_owner = owner;
}
#endregion Constructors
//------------------------------------------------------
//
// Public Methods
//
//------------------------------------------------------
//------------------------------------------------------
//
// Public Interface Methods
//
//------------------------------------------------------
/// <summary>
/// Finalize the composition.
/// This does not call base.Complete() because TextComposition.Complete()
/// will call TextServicesManager.CompleteComposition() directly to generate TextCompositionEvent.
/// We finalize Cicero's composition and TextStore will automatically
/// generate the proper TextComposition events.
/// </summary>
public override void Complete()
{
_pendingComplete = true;
}
//------------------------------------------------------
//
// Public Properties
//
//------------------------------------------------------
/// <summary>
/// Offset of the finalized composition text.
/// </summary>
/// <remarks>
/// This property is only meaningful during the handling of a
/// TextInput event. During a TextInputStart or TextInputUpdate event,
/// this property has a value of -1.
///
/// When read in the context of TextBox, the offset refers to unicode
/// code points. When read in the context of a RichTextBox, the offset
/// refers to FlowDocument symbols (unicode code points, TextElement edges,
/// or embedded UIElements).
/// </remarks>
public int ResultOffset
{
get
{
return (_ResultStart == null) ? -1 : _offset;
}
}
/// <summary>
/// Length of the current composition in unicode code points.
/// </summary>
/// <remarks>
/// This property is only meaningful during the handling of a
/// TextInput event. During a TextInputStart or TextInputUpdate event,
/// this property has a value of -1.
/// </remarks>
public int ResultLength
{
get
{
return (_ResultStart == null) ? -1 : _length;
}
}
/// <summary>
/// Offset of the composition text.
/// </summary>
/// <remarks>
/// This property is only meaningful during the handling of a
/// TextInputStart or TextInputUpdate event. During a TextInput event,
/// this property has a value of -1.
///
/// When read in the context of TextBox, the offset refers to unicode
/// code points. When read in the context of a RichTextBox, the offset
/// refers to FlowDocument symbols (unicode code points, TextElement edges,
/// or embedded UIElements).
/// </remarks>
public int CompositionOffset
{
get
{
return (_CompositionStart == null) ? -1 : _offset;
}
}
/// <summary>
/// Length of the current composition in unicode code points.
/// </summary>
/// <remarks>
/// This property is only meaningful during the handling of a
/// TextInputStart or TextInputUpdate event. During a TextInput event,
/// this property has a value of -1.
/// </remarks>
public int CompositionLength
{
get
{
return (_CompositionStart == null) ? -1 : _length;
}
}
//------------------------------------------------------
//
// Internal Methods
//
//------------------------------------------------------
internal static void CompleteCurrentComposition(UnsafeNativeMethods.ITfDocumentMgr documentMgr)
{
UnsafeNativeMethods.ITfContext context;
documentMgr.GetBase(out context);
UnsafeNativeMethods.ITfCompositionView composition = GetComposition(context);
if (composition != null)
{
UnsafeNativeMethods.ITfContextOwnerCompositionServices compositionService = context as UnsafeNativeMethods.ITfContextOwnerCompositionServices;
// Terminate composition if there is a composition view.
compositionService.TerminateComposition(composition);
Marshal.ReleaseComObject(composition);
}
Marshal.ReleaseComObject(context);
}
internal static UnsafeNativeMethods.ITfCompositionView GetCurrentCompositionView(UnsafeNativeMethods.ITfDocumentMgr documentMgr)
{
UnsafeNativeMethods.ITfContext context;
documentMgr.GetBase(out context);
UnsafeNativeMethods.ITfCompositionView view = GetComposition(context);
Marshal.ReleaseComObject(context);
return view;
}
// Set result string to TextComposition.
internal void SetResultPositions(ITextPointer start, ITextPointer end, string text)
{
Invariant.Assert(start != null);
Invariant.Assert(end != null);
Invariant.Assert(text != null);
_compositionStart = null;
_compositionEnd = null;
// We need to have another instances of TextPointer since we don't want to
// freeze original TextPointers.
_resultStart = start.GetFrozenPointer(LogicalDirection.Backward);
_resultEnd = end.GetFrozenPointer(LogicalDirection.Forward);
this.Text = text;
this.CompositionText = String.Empty;
// We must cache integer offsets -- public listeners won't expect
// them to float like TextPointers if the document changes.
_offset = (_resultStart == null) ? -1 : _resultStart.Offset;
_length = (_resultStart == null) ? -1 : _resultStart.GetOffsetToPosition(_resultEnd);
}
// Set composition string to TextComposition.
internal void SetCompositionPositions(ITextPointer start, ITextPointer end, string text)
{
Invariant.Assert(start != null);
Invariant.Assert(end != null);
Invariant.Assert(text != null);
// We need to have another instances of TextPointer since we don't want to
// freeze original TextPointers.
_compositionStart = start.GetFrozenPointer(LogicalDirection.Backward);
_compositionEnd = end.GetFrozenPointer(LogicalDirection.Forward);
_resultStart = null;
_resultEnd = null;
this.Text = String.Empty;
this.CompositionText = text;
// We must cache integer offsets -- public listeners won't expect
// them to float like TextPointers if the document changes.
_offset = (_compositionStart == null) ? -1 : _compositionStart.Offset;
_length = (_compositionStart == null) ? -1 : _compositionStart.GetOffsetToPosition(_compositionEnd);
}
//------------------------------------------------------
//
// Internal Properties
//
//------------------------------------------------------
/// <summary>
/// The result text of the text input.
/// </summary>
internal ITextPointer _ResultStart
{
get
{
return _resultStart;
}
}
/// <summary>
/// The result text of the text input.
/// </summary>
internal ITextPointer _ResultEnd
{
get
{
return _resultEnd;
}
}
/// <summary>
/// The current composition text.
/// </summary>
internal ITextPointer _CompositionStart
{
get
{
return _compositionStart;
}
}
/// <summary>
/// The current composition text.
/// </summary>
internal ITextPointer _CompositionEnd
{
get
{
return _compositionEnd;
}
}
// True if Complete has been called.
internal bool PendingComplete
{
get
{
return _pendingComplete;
}
}
// TextStore or ImmComposition that created this object.
internal object Owner
{
get
{
return _owner;
}
}
//------------------------------------------------------
//
// Internal Events
//
//------------------------------------------------------
//------------------------------------------------------
//
// Private Methods
//
//------------------------------------------------------
/// <summary>
/// Get ITfContextView of the context.
/// </summary>
private static UnsafeNativeMethods.ITfCompositionView GetComposition(UnsafeNativeMethods.ITfContext context)
{
UnsafeNativeMethods.ITfContextComposition contextComposition;
UnsafeNativeMethods.IEnumITfCompositionView enumCompositionView;
UnsafeNativeMethods.ITfCompositionView[] compositionViews = new UnsafeNativeMethods.ITfCompositionView[1];
int fetched;
contextComposition = (UnsafeNativeMethods.ITfContextComposition)context;
contextComposition.EnumCompositions(out enumCompositionView);
enumCompositionView.Next(1, compositionViews, out fetched);
Marshal.ReleaseComObject(enumCompositionView);
return compositionViews[0];
}
//------------------------------------------------------
//
// Private Fields
//
//------------------------------------------------------
// the start poisiotn of the result text
private ITextPointer _resultStart;
// the end poisiotn of the result text
private ITextPointer _resultEnd;
// the start position of the composition text
private ITextPointer _compositionStart;
// the end position of the composition text
private ITextPointer _compositionEnd;
// Composition or result offset.
private int _offset;
// Composition or result length.
private int _length;
// TextStore or ImmComposition that created this object.
private readonly object _owner;
private bool _pendingComplete;
}
}
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